Personal digital assistant
The Palm TX
EO Personal Communicator (440) from AT&T
A personal digital assistant (PDA), also known as a palmtop computer, is a mobile device which functions
as a personal information manager and has the ability to connect to the internet. The PDA has an
electronic visual display enabling it to include a web browser, but some newer models also have audio
capabilities, enabling them to be used as mobile phones or portable media players. Many PDAs can
access the internet, intranets or extranets via Wi-Fi, or Wireless Wide Area Networks (WWANs). Many
PDAs employ touch screen technology.
The term PDA was first used on January 7, 1992, by Apple Computer CEO John Sculley at the Consumer
Electronics Show in Las Vegas, Nevada, referring to the Apple Newton. In 1996, Nokia introduced the
first mobile phone with full PDA functionality, the 9000 Communicator, which has since grown to
become the world's best-selling PDA and which spawned a category of phones called the Smartphone.
Today the vast majority of all PDAs are smart phones, selling over 150 million units while non-phone
("stand-alone") PDAs sell only about 3 million units per year. The HTC, Apple iPod touch, Nokia N-Series,
and RIM BlackBerry are typical Smartphone brands.
1 Typical features
1.1 Touch screen
1.2 Memory cards
1.3 Wired connectivity
1.4 Wireless connectivity
2.1 Automobile navigation
2.2 Ruggedized PDAs
2.3 Medical and scientific uses
2.4 Educational uses
2.5 Sporting uses
2.6 PDA for people with disabilities
3 Popular consumer PDAs
5 Rugged PDAs
1 - Typical features
Currently, a typical PDA has touch screen for entering data, a memory card slot for data storage and at
least one of the following for connectivity: IrDA, Bluetooth and/or Wi-Fi. However, many PDAs (typically
those used primarily as telephones) may not have a touch screen, using soft keys, a directional pad and
either the numeric keypad or a thumb keyboard for input.
Software typically required being a PDA includes an appointment calendar, a to-do list, an address book
for contacts and some sort of note program. Connected PDAs also typically include E-mail and Web
1.1 - Touch screen
Many of the original PDAs, such as the Apple Newton and Palm Pilot, featured touch screen for user
interaction, having only a few buttons usually reserved for shortcuts to often used programs. Touch
screen PDAs, including Windows Mobile devices, usually have a detachable stylus that can be used on
the touch screen. Interaction is then done by tapping the screen to activate buttons or menu choices,
and dragging the stylus to, for example, highlight. Text input is usually done in one of four ways:
Using a virtual keyboard, where a keyboard is shown on the touch screen. Input is done by tapping
letters on the screen.
Using external keyboard or chorded keyboard connected by USB, IR or Bluetooth.
Using letter or word recognition, where letters or words are written on the touch screen, and then
"translated" to letters in the currently activated text field. Despite rigorous research and development
projects, end-users experience mixed results with this input method, with some finding it frustrating and
inaccurate, while others are satisfied with the quality. Recognition and computation of handwritten
horizontal and vertical formulas such as "1 + 2 =" was also under development.
Stroke recognition (one Palm implementation is called Graffiti). In this system a predefined set of
strokes represents the various characters used in input. The user learns to draw these strokes on the
screen or in an input area. The strokes are often simplified character shapes to make them easier for the
device to recognize.
PDAs for business use, including the BlackBerry and Palm Treo, have full keyboards and scroll wheels or
thumb wheels to facilitate data entry and navigation, in addition to supporting touch-screen input.
There are also full-size foldable keyboards available that plug directly, or use wireless technology to
interface with the PDA and allow for normal typing. BlackBerry has additional functionality, such as
push-based email and applications.
Newer PDAs, such as the Apple iPhone, iPod Touch and Palm Pre include new user interfaces using other
means of input. The iPhone and iPod touch uses a technology called Multi-touch, as does the Palm Pre
and HTC HD2.
1.2 - Memory cards
Although many early PDAs did not have memory card slots now most have either an SD (Secure Digital)
and/or a Compact Flash slot. Although originally designed for memory, SDIO and Compact Flash cards
are available for such things as Wi-Fi and Webcams. Some PDAs also have a USB port, mainly for USB
flash drives. Some PDAs are now compatible with micro SD cards, which are physically much smaller
than standard SD cards.
1.3 - Wired connectivity
While many earlier PDAs connected via serial ports or other proprietary format, many today connect via
USB cable. This served primarily to connect to a computer, and few, if any PDAs were able to connect to
each other out of the box using cables, as USB requires one machine to act as a host - functionality
which was not often planned. Some PDAs were able to connect to the internet, either by means of one
of these cables, or by using an extension card with an Ethernet port/RJ-45 adaptor.
1.4 - Wireless connectivity
Most modern PDAs have Bluetooth wireless connectivity, an increasingly popular tool for mobile
devices. It can be used to connect keyboards, headsets, GPS and many other accessories, as well as
sending files between PDAs. Many mid-range and superior PDAs have Wi-Fi/WLAN/802.11-connectivity,
used for connecting to Wi-Fi hotspots or wireless networks. Older PDAs predominantly have an IrDA
(infrared) port; however fewer current models have the technology, as it is slowly being phased out due
to support for Bluetooth and Wi-Fi. IrDA allows communication between two PDAs: a PDA and any
device with an IrDA port or adapter. Most universal PDA keyboards use infrared technology because
many older PDAs have it, and infrared technology is low-cost and has the advantage of being permitted
1.5 - Synchronization
An important function of PDAs is synchronizing data with a PC. This allows up-to-date contact
information stored on software such as Microsoft Outlook or ACT! to update the database on the PDA.
The data synchronization ensures that the PDA has an accurate list of contacts, appointments and e-
mail, allowing users to access the same information on the PDA as the host computer.
The synchronizing also prevents the loss of information stored on the device in case it is lost, stolen, or
destroyed. Another advantage is that data input is usually a lot quicker on a PC, since text input via a
touch screen is still not quite optimal. Transferring data to a PDA via the computer is therefore a lot
quicker than having to manually input all data on the handheld device.
Most PDAs come with the ability to synchronize to a PC. This is done through synchronization software
provided with the handheld, such as HotSync Manager, which comes with Palm OS handhelds, Microsoft
ActiveSync for Windows XP and older operating systems, or Windows Mobile Device Center for
Windows Vista, both of which sync with Microsoft Windows Mobile or Pocket PC devices. On Mac OS X,
the application iSync can be used for some PDAs.
These programs allow the PDA to be synchronized with a Personal information manager. This personal
information manager may be an outside program or a proprietary program. For example, the BlackBerry
PDA comes with the Desktop Manager program which can synchronize to both Microsoft Outlook and
ACT. Other PDAs come only with their own proprietary software. For example, some early Palm OS PDAs
came only with Palm Desktop while later Palms such as the Treo 650 has the built-in ability to sync to
Palm Desktop and/or Microsoft Outlook, while Microsoft's ActiveSync and Windows Mobile Device
Center only synchronize with Microsoft Outlook or a Microsoft Exchange server.
Third-party synchronization software is also available for many PDAs from companies like Intellisync and
Companion Link. This software synchronizes these handhelds to other personal information managers
which are not supported by the PDA manufacturers, such as Goldmine and IBM Lotus Notes.
2 – Uses
PDAs are used to store information that can be accessed at anytime and anywhere.
2.1 - Automobile navigation
Many PDAs are used in car kits and are fitted with differential Global Positioning System (GPS) receivers
to provide real time automobile navigation. PDAs are increasingly being fitted as standard on new cars.
Many systems can also display traffic conditions, dynamic routing and roadside mobile radar guns.
Popular software in Europe and in America for this functionality are TomTom, Garmin, iGO etc. showing
road conditions and 2D or 3D environments.
2.2 - Ruggedized PDAs
For many years businesses and government organizations have relied upon rugged PDAs also known as
enterprise digital assistants (EDAs) for mobile data applications. Typical applications include supply chain
management in warehouses, package delivery, route accounting, medical treatment and record keeping
in hospitals, facilities maintenance and management, parking enforcement, access control and security,
capital asset maintenance, meter reading by utilities, and "wireless waitress" applications in restaurants
and hospitality venues. A common feature of EDAs is the integration of Data Capture devices like Bar
Code, RFID and Smart Card Readers.
2.3 - Medical and scientific uses
In medicine, PDAs have been shown to aid diagnosis and drug selection and some studies have
concluded that their use by patients to record symptoms improves the effectiveness of communication
with hospitals during follow-up. A range of resources have been developed to cater for the demand
from the medical profession which supply drug databases, treatment information and relevant news in
formats specific to mobile devices and services such as AvantGo translate medical journals into readable
formats and provide updates from journals. Ward Watch organizes medical records to remind doctors
making ward rounds of information such as the treatment regimens of patients and programs. Finally,
Pendragon and Spyware provide tools for conducting research with mobile devices, and connecting to a
central server allowing the user to enter data into a centralized database using their PDA. Additionally,
Microsoft Visual Studio and Sun Java provide programming tools for developing survey instruments on
the handheld. These development tools allow for integration with SQL databases that are stored on the
handheld and can be synchronized with a desktop/server based database.
Recently the development of Sensor Web technology has led to discussion of using wearable bodily
sensors to monitor ongoing conditions like diabetes and epilepsy and alerting medical staff or the
patient themselves to the treatment required via communication between the web and PDAs.
2.4 - Educational uses
As mobile technology becomes more common, it is increasingly being used as a learning tool. Some
educational institutions have integrated PDAs into their teaching practices (MLearning).
PDAs and handheld devices are commonly allowed in the classroom for digital note taking. Students can
spell-check, modify, and amend their class notes or e-notes. Some educators distribute course material
through the use of the internet connectivity or infrared file sharing functions of the PDA. Textbook
publishers have begun to release e-books, or electronic textbooks, which can be uploaded directly to a
PDA, reducing the number of textbooks students must carry.
Software companies have developed programs to meet the instructional needs of educational
institutions such as dictionaries, thesauri, word processing software, encyclopedias and digital planning
2.5 - Sporting uses
PDAs may also be used by music enthusiasts. They can be used to play a variety of file formats (unlike
most MP3 Players) during physical exercise (e.g. running), unlike certain larger devices such as laptops.
PDAs can be used by road rally enthusiasts. PDA software can be used for calculating distance, speed,
time, and GPS navigation as well as unassisted navigation.
PDA's may be used to plan decompression dive profiles, use of mixtures up to 100% oxygen with
programmes such as V-planner. Nitrox, Trimix, TriOx, HeliOx, OC, SCR, CCR, RB80, KISS and multilevel
2.6 - PDA for people with disabilities
PDAs offer varying degrees of accessibility for people with differing abilities, based on the particular
device and service. People with vision, hearing, mobility, and speech impairments may be able to use
PDAs on a limited basis, and this may be enhanced by the addition of accessibility software (e.g. speech
recognition for verbal input instead of manual input). Universal design is relevant to PDAs as well as
other technology, and a viable solution for many user-access issues, though it has yet to be consistently
integrated into the design of popular consumer PDA devices.
PDAs have recently become quite useful in the Traumatic brain injury/Posttraumatic stress disorder
population, especially seen in troops returning home from Operation Iraqi Freedom(OIF)/Operation
Enduring Freedom(OEF). PDAs address memory issues and help these men and women out with daily
life organization and reminders. As of quite recently, the Department of Veterans' Affairs (VA) has begun
issuing thousands of PDAs to troops who present the need for them. Occupational therapists have taken
on a crucial role within this population helping these veterans return to the normality of life they once
3 - Popular consumer PDAs
Abacus PDA Watch
Acer N Series
Fujitsu Siemens Computers Loox
HTC Corporation (Dopod, Qtek)'s series of Windows Mobile PDA/phones (HTC)
HTC, especially the HTC P3470 aka Pharos
Palm, Inc. (Tungsten E2, TX, Treo, Zire Handheld, and Pre)
Pocket Mail (email PDA with inbuilt acoustic coupler)
Psion - obsolete
Sharp Wizard and Sharp Zaurus - obsolete
4 - Discontinued
Earlier Palm Handhelds
HP Jornada Pocket PC (phased out/merged with iPAQ line in 2002)
Compaq iPAQ Merged with HP iPAQ in 2000
Osaris running EPOC OS distributed by Oregon Scientific
Casio Pocket Viewer
Roland PMA-5 (Personal Music Assistant)
Tap wave Zodiac
Sony Magic Link with the Magic Cap operating system
5 - Rugged PDAs
American industrial systems (Mil-Spec, IP67)
Data logic Mobile
Hand Held Products (HHP)